Bug still occurs in version 1.8.8 However, the option -w 65535 fixes the issue.
$ h5dump -w 65535 plain.hdf5 > /dev/null && echo $? 0 -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
